Eight children and a security guard have been killed in a rare school shooting in Serbia, officials say.
The suspect is a 14-year-old seventh grade student.
Police in central Belgrade received a call about the shooting at the Vladislav Ribnikar school about 8:40am (06:40 GMT) on Wednesday, they said in a statement.
The accused teenager fired several shots from his father’s gun at other students and the school guard.
At least one of six injured pupils was in a life-threatening condition and was undergoing surgery, reports said, while a teacher was also seriously wounded.
Milan Nedeljkovic, mayor of the central Vracar district, where the school is located, said doctors were fighting to save the teacher’s life.
As news of the shooting spread, terrified parents arrived at the school to try to find their children.
Milan Milosevic, who said his daughter was in a history class when the shooting took place, told N1 television that he rushed out when he heard what had happened.
“I asked, ‘Where is my child?’ but no one could tell me anything at first,” he said. “Then she called, and we found out she was out.”
“He [the shooter] fired first at the teacher and then the children who ducked under the desks,” Milosevic quoted his daughter as saying. “She said he was a quiet boy and a good student.”
Officers in helmets and bulletproof vests cordoned off the area around the school.
“I saw kids running out from the school, screaming,” a girl who attends a high school adjacent to Vladislav Ribnikar told state TV RTS. “Parents came. They were in panic. Later, I heard three shots.”
Local media footage from the scene showed commotion outside the school as police removed the suspect, whose head was covered as officers led him to a car parked in the street.
Mass shootings are relatively rare in Serbia, which has strict gun laws, but the Western Balkans are awash with hundreds of thousands of illegal weapons after wars and unrest in the 1990s.
In the last mass shooting, a Balkan war veteran in 2013 killed 13 people in a central Serbian village.
Serbian authorities have offered several amnesties for owners to hand in or register illegal guns.